When you buy a diamond, or diamond jewellery price is not the only consideration. You want something that looks great, that gives aesthetic pleasure, that satisfies you and makes you feel proud to own it. How would you feel if you bought a lovely diamond ring, only to find out months or years later that the piece that was so proudly worn was not a real diamond at all? What if your diamond was of much lower quality than you had been told and paid for?

You would be angry, disappointed and more than a little bitter.These days, such disappointments are rare because of a jeweller called Robert Shipley and what he did to change the diamond industry trade. Before the 1920s, buying diamond jewellery either required a great deal of skill, or the good fortune to be dealing with honest jewellers who chose not to mislead their clients. Robert Shipley decided that this was not good enough. He set up a gemmology course to train jewellers so that they could give better service to their clients and then in 1931 he established the Gemological Institute of America.

The GIA is a non-profit organisation that, among other services, carries out independent and impartial diamond grading on a large portion of the world's jewellery diamonds.

The GIA and the 4Cs

As most people who have ever bought diamond jewellery know, diamonds are assessed and rated according to the 4Cs of Clarity, Colour, Cut and Carat Weight. The 4Cs concept was devised by the GIA in 1953 and is now universal across the diamond industry. Every jeweller and diamond seller uses them when discussing and selling diamonds.

The 4Cs are a set of grading scales that enable a skilled diamond grader to report on these critical aspects of a diamond's quality. All diamond grading labs use a similar set of scales but sometimes with different terminology or differing cut-off points.

What Are The GIA Grading Scales?

The cut of a diamond is about the quality of the cutting of the diamond and takes account of the proportions, symmetry, the angles used, the brilliance, fire, scintillation and the quality of the finish of the diamond.

Most diamonds used in jewellery are clear or white. The clearest, whitest diamonds are the most prized, rare and valuable. For typical buyers without training, it can be hard to tell the difference between the colour of two apparently similar stones. The price difference between the two can be significant. The GIA colour grading scale enables buyers to make a choice and to buy the right diamond for their needs and budget.

Clarity refers to the flaws and of a diamond. Internal flaws are called inclusions, and external flaws are called blemishes. The fewer defects a diamond has the higher its value. A heavily flawed diamond might have clearly visible inclusions that might even affect the durability of the stone.

Carat is a measure of the weight of a diamond. 1 Carat is 200 milligrams. When you buy a diamond, knowing the weight of the gem is important because two diamonds of identical weight can be cut in such a way that they seem to have a different size.

A GIA report also carries information about the proportions of the diamond, the polish, the positions of inclusions and blemishes, fluorescence and symmetry.

A GIA report can be had for any stone larger than 0.15 carats. Many jewellers do not obtain grading reports for small stones due to the cost in relation to the selling price.

The Types Of GIA Grading Report

In most cases, the report on a diamond will have already been created by the jeweller or diamond merchant. A buyer is unlikely to order an additional report format to the one offered. However, the GIA provides several report types.

1. Diamond Grading Report. Covers all the necessary information about a diamond that you are planning to buy.
2. The Diamond Dossier. This includes a laser inscription of the diamond identifying it permanently and tying it conclusively to the grading report. The laser identification is useful in case of theft.
3. Diamond Focus Report. An online service using the same standards as the physical reports. The Focus Report is designed for smaller, round cut, diamonds between 0.15 and 0.29 carats.
4. Diamond Origin Report. This version adds information about the country of origin of the diamond, an inscribed identification on the girdle of the stone for identification and tracking. There are images of the diamond in both rough and polished condition.

Can You Trust A GIA Grading Report?

The GIA is an independent agency with a worldwide network of grading labs. All the labs work to the same exacting standards making reports from all labs consistent. The GIA has no part in the sales of diamonds, they are paid to create grading reports with no financial interest in the sale of any diamonds that they grade. As with any human creation, the GIA is not perfect, mistakes are occasionally made.

The GIA's success is founded upon its impartiality and authority as gemmological experts, this makes them entirely trustworthy for any buyer of diamonds or diamond jewellery.

What To Watch Out For

1. Check the date the report was issued
2. Check that the cut and shape of the stone match the stone you are looking at
3. Do the sizes of the diamond match those on the report?
4. Make sure the report carries a unique report number
5. Check the clarity and colour grading of the stone. DO they meet your needs? Do they match the diamond you are checking out?
6. Each GIA report carries a QR code that identifies the report as genuine. You should check this using an app on your smartphone.

Why Should You Buy A GIA Graded Diamond?

A GIA diamond report is not an appraisal of value, it is an objective description of the characteristics of the diamond. The purpose of buying a quality graded diamond is to ensure that you get what you pay for. The reputation of the report is the highest in the industry, making it acceptable as the basis of valuations for insurance or sales purposes.

Consistency from one report, one diamond, to the next, ensures that buyers can trust GIA reports. Each diamond's grading will have been checked and confirmed by multiple experts before the final report is created.

When your diamond has a GIA report, you will be confident that your diamond is natural, not synthetic or lab-grown. You will know about any enhancements or treatments carried out to improve its characteristics. You will be able to make an informed, confident purchase.

Because diamonds are such costly items, you need to be sure that the report is genuine, that it matches the diamond you are considering. Each GIA report has security features including QR codes that can be confirmed online, holograms and microprinting like that used on banknotes to foil counterfeiting.

Several other diamond grading labs offer similar services to those of the GIA, but none has the reputation for reliability, honesty and impartiality that GIA carries.